The Coastal Environmental Rights Foundation has lobbed another lawsuit against San Diego in the ongoing debate over regulatory oversight of fireworks -- and it doesn't appear that the disagreements will end any time soon.

The Encinitas-based group has dogged pyrotechnic displays in San Diego for the past two years in an attempt to force more environmental safeguards, particularly for displays over water at La Jolla Cove and Lake Murray. However, the legal effort has dragged in thousands of annual events because they fall under some of the same city permitting rules as fireworks shows.

On Friday, the coastal foundation levied its fourth related lawsuit. It challenged the City Council's Nov. 14 approval of municipal code changes that provide certain events, including fireworks displays, with exemptions in the permitting process at city parks.

"This is a campaign. This is not one battle," said foundation lawyer Marco Gonzalez. "We have a number of bullets left in our gun, and to the extent needed we will start to use some of these other opportunities."

Also on Friday, the foundation and the city faced off in Superior Court over a related lawsuit. No ruling was issued.

In addition, the parties have skirmished over attorney's fees, which the coastal foundation said have topped $750,000 for its side of the case. Last month, a judge said San Diego didn't have to pay that bill but she left the door open for payments pending resolution of the various suits.

“CERF has repeatedly offered to work with the city to develop a fair permitting practice – one that is not overly burdensome to event organizers, while at the same time does not abandon basic environmental protections," Gonzalez said. “Unfortunately, the city has instead chosen to vilify environmentalists, delay and avoid dealing with the issues head-on, and side-step the law."

Officials at San Diego City Hall aren't backing down.

“Marco Gonzalez seems intent on wasting as much court time as possible on his misguided campaign against July 4 fireworks," said a statement by Alex Roth, a spokesman for Mayor Jerry Sanders. "He also wants three-quarters of a million dollars in legal fees from taxpayers. I’m guessing he’ll be submitting an even bigger bill at some point, which is sad."

In court, city lawyers have defended the city's processes and have appealed a ruling against them in related litigation.

But the coastal foundation's efforts to increase environmental scrutiny have had wide ripple effects.

The San Diego Port Tenants Association won't sponsor New Year's Eve fireworks this year as it did before 2009, said president Sharon Cloward. She said the big barrier was the cost and time involved with getting permits through the San Diego Regional Water Quality Control Board.

Cloward said she's hopeful that the Port of San Diego will seek an umbrella permit for all fireworks shows over the bay so that by this time next year her association will be gearing up for a New Year's Eve show. "If we can get this resolved and make it affordable, we will be back on track," she said.